Synthehol

Synthehol (a portmanteau of "synthesized" and "alcohol") is a chemical variant of alcohol. It appears to have the same taste and smell as "real" alcohol to most individuals, but none of the deleterious effects associated with alcohol for most humanoids, such as debilitating intoxication, addiction, and alcohol poisoning. Most humanoids have an enzyme which breaks down the alcohol-like compounds in synthehol. According to Data, synthehol's "intoxicating effects can be easily dismissed." (TNG: "Relics")

On at least two occasions, Seven of Nine became intoxicated after drinking synthehol, as her Borg implants were not designed to process it. Just one champagne flute of synthehol was enough to give her a blood synthehol level of 0.5%. She suffered similar symptoms to those that alcohol has on non-assimilatedHumans. (VOY: "Timeless", "Body and Soul")

In 2375, the KadiambassadorTomin visited USS Voyager, attended a reception, and drank some syntheholic beverages. It was later realized that Kadi physiology lacks the enzyme which breaks down the alcohol-like substance in synthehol, which caused him to become drunk and attempt to woo Seven of Nine. He later passed out, and The Doctor was able to remove the synthehol with Seven's nanoprobes. (VOY: "Someone to Watch Over Me")